Radiation effects on DNA content of cervical cancer cells: A rapid evaluation of radiation sensitivity by laser scanning cytometry

Impact of radiation source activity on short- and long-term outcomes of cervical carcinoma patients treated with high-dose-rate brachytherapy: A retrospective cohort study

OBJECTIVE

High-dose-rate (HDR) afterloading brachytherapy using Iridium-192 source involves large radiation activity varieties due to fast decay. It was unknown but clinically desirable to evaluate its impacts on patient outcomes to support more informed decisions.

METHODS

Data of 510 cervical carcinoma (CC) patients were retrospectively included. High-radioactive (HR) and low-radioactive (LR) groups were statistically defined per patient-specific average mean-dose-rate (MDR) of all fractions. The cutoffs were calculated using R-3.6.1 packages based on significance of correlation with binary outcome or survival time. Categorized 1-month and 3-month follow-up results were analyzed as short-term outcomes. Long-term outcomes were evaluated using local recurrence-free survival (LRFS) and metastatic recurrence-free survival (MRFS). Propensity-score-matched (PSM) pairs were generated to reduce bias.

RESULTS

The median follow-up time was 47.1 months (interquartile range: 33.9 months-66.4 months), involving MDR varieties of up to 9 folds ranging from 6059.99 cGy/h to 54013.66 cGy/h due to 17 source replacements at intervals ranging from 93 days-199 days. Both short-term (1-month: p = 0.22; 3-month: p = 0.79) and long-term (LRFS: p = 0.10; MRFS: p = 0.46) outcomes showed no significant difference between HR and LR. Subgroup analysis displayed significantly better results in LR for stage I-II (3-month, p = 0.02) and stage II (LRFS, p = 0.04) patients. Both LRFS and MRFS of LR were significantly non-inferior to HR (p ≤ 0.02).

CONCLUSIONS

LR is clinically non-inferior or partially superior to HR for CC treatment using HDR, which dispels concerns of potentially undermined patient outcomes when source replacement is delayed.

IER5 as a promising predictive marker promotes irradiation-induced apoptosis in cervical cancer tissues from patients undergoing chemoradiotherapy

Purpose

To define the role of immediate-early 5 (IER5) gene as a promising biomarker in predicting the radiosensitivity and prognosis of cervical cancer patients receiving cisplatin-based concurrent chemoradiotherapy (DDP-CCRT).

Results

Our investigations found that IER5 level was markedly elevated in cervical cancer patients after being treated with irradiation, which indicated IER5 was closely dose induced. By contrast, the correlation between IER5 and radiosensitivity cannot be confirmed by the present study. The up-regulation of IER5 expression effectively increased cell apoptosis after administration of irradiation (P < 0.05). Using an ANOVA model for repeated-measures, we found significant association between the IER5 level and tumor size (P < 0.05).

Materials and Methods

Forty-three cervical cancer patients stage II_b-III_b received DDP-CCRT were registered. Biopsy tissues were obtained after administration of irradiation dose of 0 Gy, 2~6 Gy, 10 Gy, 20 Gy, 30 Gy, respectively. The IER5 protein and mRNA levels were measured by immunohistochemistry, western blot and quantitative polymerase chain reaction, respectively; besides, the apoptosis rate was assessed by transferase-mediated dUTP nick end labeling.

Conclusions

Mechanistically, we confirmed that IER5 induced by radiation dose enhanced apoptosis of cervical cancer, was inversely associated with tumor size. In conclusion, our studies indicate target IER5 is improved to be a potential radiosensitizer for developing effective therapeutic strategies against cervical cancer to radiotherapy and a predictive biomarker for radiosensitivity.

Prognostic significance of S-phase fractions in peritumoral invading zone analyzed by laser scanning cytometry in patients with high-grade glioma: A preliminary study

The predominant characteristic of malignant glioma is the presence of invading tumor cells in the peritumoral zone. Distinguishing between tumor cells and normal cells in a peritumoral lesion is challenging. Therefore, the aim of the present study was to investigate the cell-cycle phase measurements of fixed paraffin-embedded specimens from the peritumoral invading zone of high-grade gliomas using laser scanning cytometry. A total of 12 high-grade gliomas (2 anaplastic astrocytomas and 10 glioblastomas) were studied. The tumor core and peritumoral invading zone of each tumor specimen were investigated. Tissue sections (50 µm) from the paraffin blocks were deparaffinized, rehydrated and enzymatically disintegrated, and the cells in suspension were stained with propidium iodide and placed on microscope slides. A slight trend for an increased S-phase fraction in the peritumoral invading zone compared with the tumor core was observed (P=0.24). Additionally, there was a trend for a decrease in the overall survival time of patients with increasing peritumoral invading zone S-phase fraction (P=0.12). These data suggest that laser scanning cytometry is a powerful and clinically relevant tool for the objective analysis of the cell cycle in malignant gliomas.